ˈjack-staff Naut.
[f. jack n.3 + staff.]
1. A short staff, usually set upon the bowsprit or at the bow of a ship, on which the flag called the jack (jack n.3) is hoisted.
| 1692 Capt. Smith's Seaman's Gram. i. xiv. 65 Jack staff and Jack. 1794 Rigging & Seamanship I. 175 The Jack⁓staff is a short staff erected on the aftside of the bowsprit⁓cap, to expand the jack. 1880 Preble Hist. of Flag (ed. 2) v. 509 The stars and stripes for the stern, the boat-flag for the jackstaff, and two blue flags for the wheel-houses. |
2. Used (? erron.) for Jacob's staff (sense 2 a).
| 1891 J. Winsor Columbus xi. 261 Whether the cross-staff or Jackstaff, a seaboard implement somewhat more convenient than the astrolabe, was known to Columbus is not very clear. |